/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.solr.schema;

import java.io.IOException;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.lucene.index.DocValuesSkipIndexType;
import org.apache.lucene.index.DocValuesType;
import org.apache.lucene.index.IndexOptions;
import org.apache.lucene.index.IndexableField;
import org.apache.lucene.index.IndexableFieldType;
import org.apache.lucene.index.VectorEncoding;
import org.apache.lucene.index.VectorSimilarityFunction;
import org.apache.lucene.search.SortField;
import org.apache.solr.common.SolrException;
import org.apache.solr.common.util.SimpleOrderedMap;
import org.apache.solr.response.TextResponseWriter;

/** Encapsulates all information about a Field in a Solr Schema */
public final class SchemaField extends FieldProperties implements IndexableFieldType {
  private static final String FIELD_NAME = "name";
  private static final String TYPE_NAME = "type";
  private static final String DEFAULT_VALUE = "default";

  final String name;
  final FieldType type;
  final int properties;
  final String defaultValue;
  boolean required = false; // this can't be final since it may be changed dynamically

  /** Declared field property overrides */
  Map<String, Object> args = Collections.emptyMap();

  /**
   * Create a new SchemaField with the given name and type, using all the default properties from
   * the type.
   */
  public SchemaField(String name, FieldType type) {
    this(name, type, type.properties, null);
  }

  /**
   * Create a new SchemaField from an existing one by using all of the properties of the prototype
   * except the field name.
   */
  public SchemaField(SchemaField prototype, String name) {
    this(name, prototype.type, prototype.properties, prototype.defaultValue);
    args = prototype.args;
  }

  /**
   * Create a new SchemaField with the given name and type, and with the specified properties.
   * Properties are *not* inherited from the type in this case, so users of this constructor should
   * derive the properties from type.getSolrProperties() using all the default properties from the
   * type.
   */
  public SchemaField(String name, FieldType type, int properties, String defaultValue) {
    this.name = name;
    this.type = type;
    this.properties = properties;
    this.defaultValue = defaultValue;

    // initialize with the required property flag
    required = (properties & REQUIRED) != 0;

    type.checkSchemaField(this);
  }

  public String getName() {
    return name;
  }

  public FieldType getType() {
    return type;
  }

  public int getProperties() {
    return properties;
  }

  public boolean isUninvertible() {
    return (properties & UNINVERTIBLE) != 0;
  }

  public boolean indexed() {
    return (properties & INDEXED) != 0;
  }

  @Override
  public boolean stored() {
    return (properties & STORED) != 0;
  }

  public boolean hasDocValues() {
    return (properties & DOC_VALUES) != 0;
  }

  public boolean storeTermVector() {
    return (properties & STORE_TERMVECTORS) != 0;
  }

  public boolean storeTermPositions() {
    return (properties & STORE_TERMPOSITIONS) != 0;
  }

  public boolean storeTermOffsets() {
    return (properties & STORE_TERMOFFSETS) != 0;
  }

  public boolean storeTermPayloads() {
    return (properties & STORE_TERMPAYLOADS) != 0;
  }

  @Override
  public boolean omitNorms() {
    return (properties & OMIT_NORMS) != 0;
  }

  public boolean omitTermFreqAndPositions() {
    return (properties & OMIT_TF_POSITIONS) != 0;
  }

  public boolean omitPositions() {
    return (properties & OMIT_POSITIONS) != 0;
  }

  public boolean storeOffsetsWithPositions() {
    return (properties & STORE_OFFSETS) != 0;
  }

  public boolean useDocValuesAsStored() {
    return (properties & USE_DOCVALUES_AS_STORED) != 0;
  }

  public boolean multiValued() {
    return (properties & MULTIVALUED) != 0;
  }

  public boolean sortMissingFirst() {
    return (properties & SORT_MISSING_FIRST) != 0;
  }

  public boolean sortMissingLast() {
    return (properties & SORT_MISSING_LAST) != 0;
  }

  public boolean isRequired() {
    return required;
  }

  public boolean isLarge() {
    return (properties & LARGE_FIELD) != 0;
  }

  public Map<String, ?> getArgs() {
    return Collections.unmodifiableMap(args);
  }

  // things that should be determined by field type, not set as options
  boolean isTokenized() {
    return (properties & TOKENIZED) != 0;
  }

  boolean isBinary() {
    return (properties & BINARY) != 0;
  }

  public IndexableField createField(Object val) {
    return type.createField(this, val);
  }

  public List<IndexableField> createFields(Object val) {
    return type.createFields(this, val);
  }

  /**
   * If true, then use {@link #createFields(Object)}, else use {@link #createField} to save an extra
   * allocation
   *
   * @return true if this field is a poly field
   */
  public boolean isPolyField() {
    return type.isPolyField();
  }

  @Override
  public String toString() {
    return name
        + "{type="
        + type.getTypeName()
        + ((defaultValue == null) ? "" : (",default=" + defaultValue))
        + ",properties="
        + propertiesToString(properties)
        + (required ? ", required=true" : "")
        + "}";
  }

  public void write(TextResponseWriter writer, String name, IndexableField val) throws IOException {
    // name is passed in because it may be null if name should not be used.
    type.write(writer, name, val);
  }

  /**
   * Delegates to the FieldType for this field
   *
   * @see FieldType#getSortField
   */
  public SortField getSortField(boolean top) {
    return type.getSortField(this, top);
  }

  /**
   * Expert/advanced method to get the field {@link org.apache.lucene.codecs.PostingsFormat}.
   *
   * @return The {@code postingsFormat} declared; or null if unspecified.
   */
  public String getPostingsFormat() {
    return (String) args.getOrDefault(POSTINGS_FORMAT, type.getPostingsFormat());
  }

  /**
   * Expert/advanced method to get the field {@link org.apache.lucene.codecs.DocValuesFormat}.
   *
   * @return The {@code docValuesFormat} declared; or null if unspecified.
   */
  public String getDocValuesFormat() {
    return (String) args.getOrDefault(DOC_VALUES_FORMAT, type.getDocValuesFormat());
  }

  /**
   * Sanity checks that the properties of this field type are plausible for a field that may be used
   * in sorting, throwing an appropriate exception (including the field name) if it is not.
   * FieldType subclasses can choose to call this method in their getSortField implementation
   *
   * @see FieldType#getSortField
   */
  public void checkSortability() throws SolrException {
    if (multiValued()
        // if either of these are non-null, then we should not error
        && null == this.type.getDefaultMultiValueSelectorForSort(this, true)
        && null == this.type.getDefaultMultiValueSelectorForSort(this, false)) {

      throw new SolrException(
          SolrException.ErrorCode.BAD_REQUEST,
          "can not sort on multivalued field: "
              + getName()
              + " of type: "
              + this.type.getTypeName());
    }
    if (!hasDocValues()) {
      if (!(indexed() && isUninvertible() && null != this.type.getUninversionType(this))) {
        throw new SolrException(
            SolrException.ErrorCode.BAD_REQUEST,
            "can not sort on a field w/o docValues unless it is indexed=true uninvertible=true and the type supports Uninversion: "
                + getName());
      }
    }
  }

  /**
   * Sanity checks that the properties of this field type are plausible for a field that may be used
   * to get a {@link org.apache.lucene.queries.function.valuesource.FieldCacheSource}, throwing an
   * appropriate exception (including the field name) if it is not. FieldType subclasses can choose
   * to call this method in their getValueSource implementation
   *
   * @see FieldType#getValueSource
   */
  public void checkFieldCacheSource() throws SolrException {
    if (multiValued()) {
      throw new SolrException(
          SolrException.ErrorCode.BAD_REQUEST,
          "can not use FieldCache on multivalued field: " + getName());
    }
    if (!hasDocValues()) {
      if (!(indexed() && isUninvertible() && null != this.type.getUninversionType(this))) {
        throw new SolrException(
            SolrException.ErrorCode.BAD_REQUEST,
            "can not use FieldCache on a field w/o docValues unless it is indexed uninvertible=true and the type supports Uninversion: "
                + getName());
      }
    }
  }

  static SchemaField create(String name, FieldType ft, Map<String, ?> props) {

    String defaultValue = null;
    if (props.containsKey(DEFAULT_VALUE)) {
      defaultValue = (String) props.get(DEFAULT_VALUE);
    }
    SchemaField field = new SchemaField(name, ft, calcProps(name, ft, props), defaultValue);
    field.args = new HashMap<>(props);
    return field;
  }

  /**
   * Create a SchemaField w/ the props specified. Does not support a default value.
   *
   * @param name The name of the SchemaField
   * @param ft The {@link org.apache.solr.schema.FieldType} of the field
   * @param props The props. See {@link #calcProps(String, org.apache.solr.schema.FieldType,
   *     java.util.Map)}
   * @param defValue The default Value for the field
   * @return The SchemaField
   * @see #create(String, FieldType, java.util.Map)
   */
  static SchemaField create(String name, FieldType ft, int props, String defValue) {
    return new SchemaField(name, ft, props, defValue);
  }

  static int calcProps(String name, FieldType ft, Map<String, ?> props) {
    int trueProps = parseProperties(props, true, true);
    int falseProps = parseProperties(props, false, true);

    int p = ft.properties;

    //
    // If any properties were explicitly turned off, then turn off other properties
    // that depend on that.
    //
    if (on(falseProps, STORED)) {
      int pp = STORED | BINARY | LARGE_FIELD;
      if (on(pp, trueProps)) {
        throw new RuntimeException(
            "SchemaField: " + name + " conflicting stored field options:" + props);
      }
      p &= ~pp;
    }

    if (on(falseProps, INDEXED)) {
      int pp =
          (INDEXED
              | STORE_TERMVECTORS
              | STORE_TERMPOSITIONS
              | STORE_TERMOFFSETS
              | STORE_TERMPAYLOADS
              | UNINVERTIBLE);
      if (on(pp, trueProps)) {
        throw new RuntimeException(
            "SchemaField: "
                + name
                + " conflicting 'true' field options for non-indexed field:"
                + props);
      }
      p &= ~pp;
    }

    if (on(falseProps, UNINVERTIBLE) && on(falseProps, DOC_VALUES)) {
      int pp = (SORT_MISSING_FIRST | SORT_MISSING_LAST);
      if (on(pp, trueProps)) {
        throw new RuntimeException(
            "SchemaField: "
                + name
                + " conflicting 'true' field options for non-docValues/non-uninvertible field:"
                + props);
      }
      p &= ~pp;
    }

    if (on(falseProps, INDEXED)) {
      int pp = (OMIT_NORMS | OMIT_TF_POSITIONS | OMIT_POSITIONS);
      if (on(pp, falseProps)) {
        throw new RuntimeException(
            "SchemaField: "
                + name
                + " conflicting 'false' field options for non-indexed field:"
                + props);
      }
      p &= ~pp;
    }

    if (on(trueProps, OMIT_TF_POSITIONS)) {
      int pp = (OMIT_POSITIONS | OMIT_TF_POSITIONS);
      if (on(pp, falseProps)) {
        throw new RuntimeException(
            "SchemaField: " + name + " conflicting tf and position field options:" + props);
      }
      p &= ~pp;
    }

    if (on(falseProps, STORE_TERMVECTORS)) {
      int pp = (STORE_TERMVECTORS | STORE_TERMPOSITIONS | STORE_TERMOFFSETS | STORE_TERMPAYLOADS);
      if (on(pp, trueProps)) {
        throw new RuntimeException(
            "SchemaField: " + name + " conflicting termvector field options:" + props);
      }
      p &= ~pp;
    }

    // override sort flags
    if (on(trueProps, SORT_MISSING_FIRST)) {
      p &= ~SORT_MISSING_LAST;
    }

    if (on(trueProps, SORT_MISSING_LAST)) {
      p &= ~SORT_MISSING_FIRST;
    }

    p &= ~falseProps;
    p |= trueProps;
    return p;
  }

  public String getDefaultValue() {
    return defaultValue;
  }

  @Override
  public int hashCode() {
    return name.hashCode();
  }

  @Override
  public boolean equals(Object obj) {
    return (obj instanceof SchemaField) && name.equals(((SchemaField) obj).name);
  }

  /**
   * Get a map of property name -&gt; value for this field. If showDefaults is true, include default
   * properties (those inherited from the declared property type and not overridden in the field
   * declaration).
   */
  public SimpleOrderedMap<Object> getNamedPropertyValues(boolean showDefaults) {
    SimpleOrderedMap<Object> properties = new SimpleOrderedMap<>();
    properties.add(FIELD_NAME, getName());
    properties.add(TYPE_NAME, getType().getTypeName());
    if (showDefaults) {
      if (null != getDefaultValue()) {
        properties.add(DEFAULT_VALUE, getDefaultValue());
      }
      properties.add(getPropertyName(INDEXED), indexed());
      properties.add(getPropertyName(STORED), stored());
      properties.add(getPropertyName(DOC_VALUES), hasDocValues());
      properties.add(getPropertyName(STORE_TERMVECTORS), storeTermVector());
      properties.add(getPropertyName(STORE_TERMPOSITIONS), storeTermPositions());
      properties.add(getPropertyName(STORE_TERMOFFSETS), storeTermOffsets());
      properties.add(getPropertyName(STORE_TERMPAYLOADS), storeTermPayloads());
      properties.add(getPropertyName(OMIT_NORMS), omitNorms());
      properties.add(getPropertyName(OMIT_TF_POSITIONS), omitTermFreqAndPositions());
      properties.add(getPropertyName(OMIT_POSITIONS), omitPositions());
      properties.add(getPropertyName(STORE_OFFSETS), storeOffsetsWithPositions());
      properties.add(getPropertyName(MULTIVALUED), multiValued());
      properties.add(getPropertyName(LARGE_FIELD), isLarge());
      properties.add(getPropertyName(UNINVERTIBLE), isUninvertible());
      if (sortMissingFirst()) {
        properties.add(getPropertyName(SORT_MISSING_FIRST), sortMissingFirst());
      } else if (sortMissingLast()) {
        properties.add(getPropertyName(SORT_MISSING_LAST), sortMissingLast());
      }
      properties.add(getPropertyName(REQUIRED), isRequired());
      properties.add(getPropertyName(TOKENIZED), isTokenized());
      properties.add(getPropertyName(USE_DOCVALUES_AS_STORED), useDocValuesAsStored());
      // The BINARY property is always false
      // properties.add(getPropertyName(BINARY), isBinary());
    } else {
      for (Map.Entry<String, ?> arg : args.entrySet()) {
        String key = arg.getKey();
        Object value = arg.getValue();
        if (key.equals(DEFAULT_VALUE)) {
          properties.add(key, value);
        } else {
          boolean boolVal =
              value instanceof Boolean ? (Boolean) value : Boolean.parseBoolean(value.toString());
          properties.add(key, boolVal);
        }
      }
    }
    return properties;
  }

  @Override
  public boolean tokenized() {
    return isTokenized();
  }

  @Override
  public boolean storeTermVectors() {
    return storeTermVector();
  }

  @Override
  public boolean storeTermVectorOffsets() {
    return storeTermOffsets();
  }

  @Override
  public boolean storeTermVectorPositions() {
    return storeTermPositions();
  }

  @Override
  public boolean storeTermVectorPayloads() {
    return storeTermPayloads();
  }

  @Override
  public IndexOptions indexOptions() {
    if (!indexed()) {
      return IndexOptions.NONE;
    }

    IndexOptions options = IndexOptions.DOCS_AND_FREQS_AND_POSITIONS;
    if (omitTermFreqAndPositions()) {
      options = IndexOptions.DOCS;
    } else if (omitPositions()) {
      options = IndexOptions.DOCS_AND_FREQS;
    } else if (storeOffsetsWithPositions()) {
      options = IndexOptions.DOCS_AND_FREQS_AND_POSITIONS_AND_OFFSETS;
    }

    return options;
  }

  @Override
  public DocValuesType docValuesType() {
    return DocValuesType.NONE;
  }

  @Override
  public DocValuesSkipIndexType docValuesSkipIndexType() {
    return DocValuesSkipIndexType.NONE;
  }

  @Override
  public int pointDimensionCount() {
    return 0;
  }

  @Override
  public int pointIndexDimensionCount() {
    return 0;
  }

  @Override
  public int pointNumBytes() {
    return 0;
  }

  @Override
  public int vectorDimension() {
    return 0;
  }

  @Override
  public VectorEncoding vectorEncoding() {
    return VectorEncoding.BYTE;
  }

  @Override
  public VectorSimilarityFunction vectorSimilarityFunction() {
    return VectorSimilarityFunction.EUCLIDEAN;
  }

  @Override
  public Map<String, String> getAttributes() {
    return null;
  }
}
